


The Ocean calls

by CountLestannaoftheVersEmpire



Category: Haikyuu!!
Genre: Alternate Universe, Alternate Universe - Future, Angst, Character Death, Gen, Human Experimentation, I'll change the tags as the story progresses, Lots of Angst, M/M, Other Additional Tags to Be Added, its a pretty yolo fic, maybe some fluff, mermaid au, my first Haikyuu fic
Language: English
Status: In-Progress
Published: 2017-07-01
Updated: 2017-07-01
Packaged: 2018-05-22 23:49:14
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 4
Words: 4,326
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6097941
Author URL: https://archiveofourown.org/users/CountLestannaoftheVersEmpire/pseuds/CountLestannaoftheVersEmpire
Summary: <blockquote class="userstuff">
              <p>The experiments commenced on the day the world was proclaimed to be dying. The only way humanity could survive was to....adapt.</p>
            </blockquote>





	1. Prologue

**Author's Note:**

> Alright, so I just came out of Aldnoah. Zero hell somewhat and this au was sorta made for those characters but I feel it would be more fun to do something different for a change. Also because a certain someone wanted angst.

_Come Tooru_. _Come back home to where you belong. Wake up~_

An ethereal voice beckoned to Oikawa. He had been standing on a deserted beach, his feet sinking into the soft sand. The waves were crashing relentlessly against the shore with an age old force. The smell of salt and fish soothing Tooru, when he heard that voice yet again. It pulled him into the sea like a siren would but for some reason, he felt in his bones that this voice could be trusted. He took a deep breath and took the first step, following that voice. Then, a second step. As he walked in, a sudden love for the ocean swept through him. The same loving warmth that came from a mother’s embrace. He could feel it coming, no radiating from the ocean.

_Come dearest, just a little bit more. Don’t you feel it? The call of your beautiful home._

Somewhere in the back of his mind, he heard a voice screaming, telling him to get away. But soon enough, it was blocked by the sounds of crashing waves once more and the very next second, he was submerged under water. Realizing where he was, he opened his eyes and began to swim up but alas Tooru was no swimmer. His lungs were screaming for oxygen, his mind going hazy. Pain was all he could feel. It shot up his spine, his legs, his arm and his head. He opened his mouth in a silent scream, all his air floating out above the sea. The next thing he felt was the cold and then there was complete darkness.

_Yes my sweet Tooru, sleep and when you wake you’ll have a wonderful new life._

Iwaizumi Hajime stood in front of a tank and stared with horror on his face as he saw his childhood friend, slowly turning into something inhuman. He knew the experiment was meant for the sake of humanity’s survival but this….this was just cruel. He couldn’t bear seeing his friend writhing in pain within a tank full of water, needles and tubes attached to him. How many times has Hajime seen this sight? How many more times will he have to go through this? How many times had he thought of switching off all the life support his friend was on to put him out of his misery? He wished he could but he couldn’t and wouldn’t. This was not how he had wished to meet his childhood friend again.

Oikawa Tooru had gone missing at the age of seventeen without any evidence of his existence left behind. Hajime hadn’t questioned much as he had thought that Tooru had had finally found a greater city to move to with his family and to pursue his dreams. Oh was he wrong. The research facility had gotten hold of him and at the age of 21, Oikawa had been thrown into the tank after various tests to see if he was worthy of the great experiment that would save humanity. When Iwaizumi got hired, he definitely had not been expecting to see someone dear he had lost suffering in a tank.

 So many tears had fallen, so many books he had gone through, so much black coffee had been downed and yet he couldn’t think of a way to get his friend out of this. Were they even friends anymore? Tooru may have had the worst personality he had ever seen in his life but that was the very thing that had made Hajime attracted to him. Hajime started rubbing his head frustrated. Shouting at an unconscious person in a tank will do nothing. He began packing up his things and placing everything neatly into his bag. He looked over at the floating Oikawa and let out a long sigh.

“I’ll be back tomorrow … Trashykawa. You sit tight alright?”

He gave a teary smile to the unconscious person and walked out of the lab.

Within the tank, Oikawa Tooru slept without a care for what was going on in the outside world, his legs slowly forming into a tail, his nails growing into claws, his lungs turning into gills and finally his mouth growing sharper teeth.


	2. Awakening

**Summary for the Chapter:**

> He's awake but at what cost?

There was the sound of crashing waves again and…something was crackling like broken glass being carried along the seabed. It was strangely soothing. Oikawa slowly moved his fingers and looked around. He was under the ocean yet again. He looked down at himself and gasped. He had a shimmering silver tail with scales the colour of his hair here and there. He pulled up his arms and stared, there were scales on his forearms, and were those? Claws? He felt himself panic when he came to realise that nothing was making sense. He shouldn’t be under water, breathing normally like it was nothing. What was going on? Then he heard it. A loud crashing noise, of metal falling on the floor. His ears perked up, listening intently. His mind was no longer dreaming.

 

 

 

 

Iwaizumi had been sleepily making his way to the coffee machine in the lab while his co-worker Sugawara worked on the temperature controls of the tank which was holding Oikawa when he stumbled over a box full of metal back up parts for the system keeping his friend alive. The contents flew all over the place, creating a loud crashing noise. It caught his co-worker’s attention and everyone else in the lab’s attention. He slowly picked himself up and muttered a few apologies and a few ‘I’m fine’s before crouching down to collect the things that had fallen. He went over to the coffee machine and got the water boiling when Sugawara suddenly shouted, almost making him spill the hot water all over himself. He grumbled and turned around to see Suga saying something, his sleep-deprived mind couldn’t make out.

He looked over at the tank and that was when he did drop the whole boiling kettle of water on the floor and onto his legs making him shriek and jump from the sudden pain.

_Screw it, I don’t need coffee anymore._

He looked over at the tank again and he definitely had not hallucinated it. Oikawa Tooru had finally awoken, his brown eyes scanning his surroundings confused. The needles and pipes connected to him restricting his movement greatly. Hajime ran over to the tank controls to free his friend from the needles and pipes when Suga gently placed a hand over Hajime’s, silently telling him to stay calm.

“We’ll need to check his responses and if he remembers anything first and then we’ll have to see if the experiment was a success. We don’t want a repeat of what happened to Daichi do we, Iwaizumi?”

Hajime silently shook his head and took a step back to allow Sugawara to take control. He didn’t trust himself to stay calm. He was excited but who was to say Oikawa still remembered anything. He remembered the time when Suga had been like him, staring at Daichi for days on end, hoping he’ll wake up. However, Suga’s excitement to get him out of the tank system had, in the end, resulted in Daichi’s death. Sugawara had switched off the oxygen life support a little too early and Daichi had died as his gills had not fully developed yet. When he realised that he was the one responsible for his lover’s death, he had locked himself up in his apartment for days, staring at the blank ceiling while drinking and surviving on only cup noodles. When Iwaizumi had found him, he was crying uncontrollably, a picture peeking out of shattered glass of the two of them standing together, laughing with flour stuck in their hair and on their shirts. He did his best to comfort his friend and did the chores for him when possible. Six months later, Sugawara walked into the lab with a confident look on his face, as though nothing would phase him ever again. Iwaizumi had stared surprised but all Suga did was pat him on the back and say,

“I’m here since a certain friend needs my support!”

“Are you fine?” he had asked.

_You need support yourself….but you are always looking out for others before yourself…If only, you’d let me help you_

 

 Suga didn’t say anything. He just smiled and said he was perfectly fine. However, one glimpse at those eyes and Hajime knew, his friend and co-worker will probably never be the same as he was before again. Nowadays, mentioning Daichi’s name would only make Suga stare into space while his eyes started clouding up. And so, for the sake of his friend he never personally mentioned him ever again, deciding instead to throw himself into looking for a way to help his friend whom Suga was convinced he was in love with no matter how many times he refused.

Iwaizumi looked up at Oikawa, extremely happy that he was awake. The only thing nagging at the back of his mind was,

_What happens if he is a failed experiment? Would they kill him?_

Iwaizumi moves closer to the cylindrical tank and touches its cold glass surface like he had so many times before. His eyes were clouding up from tears. His childhood friend had finally awoken. That was when, Oikawa looked over at him. He was staring straight into his eyes like a predator would prey. He suddenly felt vulnerable, as though he was being judged. A sudden shiver went up Iwaizumi’s spine. The merman seemed to have decided that Hajime was not worth his attention and so he snarled yes snarled at Iwaizumi before turning away from all the researchers in the lab in what little space he had for swimming. By then, Suga had retracted all the needles and tubes away from the merman who was now pompously swimming around his little tank like a spoilt brat.

According to Hajime anyway.

_Why was I worried about this piece of trash in the first place….._

A voice that sounded suspiciously like Suga’s nagged at the back of his mind saying ‘you looovveee hiimmm~ ‘

It took all of his self-control to not tell his co-worker to shut up out loud.

His face scrunched up with anger and annoyance yet again. What did he do to deserve this?

He definitely needed that cup of coffee now. Just as he was about to walk over to the coffee machine again, someone interrupted him again. When he turned around to see that it was Suga, he glared. At that, his dear co-worker just raised his eyebrow before going on a serious rant about Oikawa’s condition. Iwaizumi heard none of it until a word from the little rant caught his attention.

“Could you repeat that?”

“Were you listening at all Iwaizumi San?” Suga raised his eyebrow yet again.

“No no will you please repeat what you said about Amnesia.” Hajime pinched the bridge of his nose and stood waiting for his colleague to continue.

“Ah yes, your friend there has a severe case of Amnesia. It hasn’t affected his personality whatsoever. However, he has forgotten important events and people of his life before the experiment which would explain his hostility to you.”

Iwaizumi groaned and sat down on a chair.

He mumbled to himself, “This is a mess.”

He looked up and noticed the experiment analysis screen blinking with a new result. Squinting, he stood up from his chair and walked towards the screen. Tooru showed no signs of being able to adapt at will. This wasn’t good news. No it was not good news at all. He looked over at his colleague worry etching his face.

 

 

The experiment….had failed

 

**Notes for the Chapter:**

> well I sure did write this one fast. The way things are going there may be more than 5 chapters but hey I have time on my hands.


	3. Loss

**Summary for the Chapter:**

> Now, Shouyou hated, absolutely hated anyone who dared disturb his meal. He looked up and glared into the stormy blue eyes of the other merman with such a heated gaze, it should’ve killed him.

The waves crashed at the back of his consciousness.

He could hear it.

He could hear the ocean calling out to him, beckoning for him to jump in and join it.

It was a beautiful song that only he could hear.

He didn’t want to open his eyes, afraid that this image and sounds would go away. He heard the music of the ocean and the crackling sand at the seabed far deep down below.

 Even the deep trenches that were a mile away called out to him, their mysterious auras enticing him.

 It gave him the promise of a new and exciting place for him to discover.

Suddenly, it stopped, all he could feel was a sudden burst of air and then he was being thrown into the water.

 He winced slightly at the sudden saltiness.

The water he was in earlier was definitely not as salty he thought.

 Slowly but surely, he opened his eyes and flexed his fingers. Water surrounded him as fish swam rapidly by.

He looked down to see his tail there, ready to take off the moment Hinata decided to swim around.

He decided to test his new tail and within seconds, he was zipping across the coral reef as though he had been born there.

His gills were flaring open and close, keeping him supplied with the very oxygen he needed to survive.

 He could feel and sense every organism near him and a few meters away from him. He could sense every little shift in the tide and currents.

The ocean wrapped itself around him, guiding him in his first few moments in his new home. It felt warm and comforting. He couldn’t exactly remember why he looked like this and how he ended up in the ocean.

However, Hinata being Hinata couldn’t concentrate on that thought anymore when he felt his stomach protest from hunger.

 A hidden instinct told him that his lunch was only two meters away. His stomach grumbled slightly louder this time.

His ears twitched to listen to the slight swish noise the fish aka his lunch made as it swum around in lazy circles not in the least bothered that its predator was nearby.

 Instinctively he reached out with his claws and swiftly killed it, only to drop it when another blur of blue and silver came crashing into him, claws outstretched to kill.

 They fell onto the bottom of the ocean floor in a clumsy heap.

Now, Shouyou hated, absolutely hated anyone who dared disturb his meal. He looked up and glared into the stormy blue eyes of the other merman with such a heated gaze, it should’ve killed him.

Of course, only if looks could kill.

However, the other merman only glared back and started cursing at Hinata.

Words that included, “Dumbass” and “Bastard”.

 Hinata felt a sudden nudge at the back of his mind, telling him that he knew this merman. He still couldn’t remember why.

Besides, why should he remember such a rude person like this one? Hinata pouts and angrily raises his fist while doing so.

He decided to poke and prod at that thought when a name came to him that seemed to belong to the idiot who had crashed into him and made him lose his lunch.

The name “Kageyama Tobio” came to his mind.

All the other did was stare at him shocked.

“K-Kageyama?” he slowly stuttered out, as though testing the name out.

The very next second, he felt wave after wave of memories flooding into his mind, of a person who was once as important to him as the moon was to the sun.

 

 

_______________________________________________________________________________

 

 

 

 

A week had passed by but to Oikawa it only felt like a few days. Everything that was going on around him was quite interesting. Especially, the spiky head guy. He always seemed to be scowling but when he is interacting with Mr. refreshing, he actually smiled sometimes. Oikawa wondered why he scowled so much.

_He’ll grow old and have white hair really early. Hmmm.. I’m going to call him Cactus chan~ He’s cute after all._

It was interesting, analyzing his new surroundings. He felt confused yes but nothing was more exciting than getting to know new people and finding ways to break them or bond with them.

He grinned to himself at the thought.

Something was off, however. He could feel it. Something told him that cactus chan was hiding a lot from him. Something he didn’t know or perhaps remember. There had been whispers going around about how the ‘experiment’ had failed.

 Looking at himself, he had guessed they were talking about him.

 A huge puzzle piece was missing in his mind, and that bothered him more than anything else. He didn’t like not being in control.

 Not one bit.

 It was fun intimidating the others and getting so much attention but……

_I don’t like the atmosphere around me. I feel vulnerable……as though if I let my guard down, they’d kill me in an instant. But why?_

He shifted around in his small space. This was a game he did not have the advantage in and it bothered him, no had been torturing him since day one. He wished the silly humans would at least explain, but he knew that an ‘experiment’ like him doesn’t deserve to know anything at this point.

They looked at him like he was a monster. Sure, some of the lady researchers swooned but they never approached him. His mind told him that normally they would but he couldn’t remember why he remembered that. Sometimes, he’d pretend to sleep in his tank. Those were the times cactus chan would surprise him. Cactus chan would come up to his tank and place his hands on the glass, as though reaching out to him. Oikawa would hear muffled sounds of sobbing sometimes coming from outside the tank. This made him think...

_He knows something. Something that has to do with me not remembering very important things but why is he crying? I have this sudden urge to comfort him…_

He didn’t. All he could do was guess and since he didn’t have a lot of things to do he kept guessing.

_Maybe I was important to him…..but what does it matter, if he is sided with the people who treat me like a monster….an ‘experiment’ why should I care._

They gave him food like one would to a shark in an aquarium, with caution. It annoyed him quite a lot. There was no point in him attacking them, right? If he did, they’d all kill him anyways. He had claws and fangs yes. However, they had more powerful things. It was better to lay low. After all, they controlled the environment he lived in, and that was another thing that put him at great unease.

What annoyed him more was, that they gave him fish that was already killed beforehand. His claws were something he had yet to get used to, however, something within him yearned to hunt for food. Having it handed to him dead had hurt his pride immensely. On the other hand, he didn’t understand why it had upset him so much as well.

He did know one thing,

_I hate this place._

________________________________________________________________________________

Iwaizumi banged his head on the desk and made an incoherent noise as he looked at the test results yet again. Oikawa still showed no signs of being able to adapt at will. This was worrying him to no end. Not to mention the fact that his dear best friend still couldn’t remember him. He shouldn’t be expecting anything amazing from Oikawa at all. It was a miracle he had survived in the first place.

According to the records, Oikawa was the second human to have survived the metamorphosis. The very first one was called, Hinata Shouyou apparently. The records indicated that this Hinata had not suffered from much pain during the experiment. At the very last paragraph, Iwaizumi noticed that this boy had been a very hyperactive sample. After that, there was nothing written besides,

“The officials took him away the very next day.”

Hajime leaned back onto his reclining chair and pinched his nose. None of the records ever mentioned what happened to said sample after the experiment at all. That, in particular, annoyed Iwaizumi to no end.

_There is no point in conducting further investigation on a failed experiment. I have a bad feeling about this._

 A few years ago, certain predictions were made by the world organization of researchers that, in a century or so, the world will fall into chaotic imbalance that required humanity to be able to adapt to any changes faster than they do now.

Hajime decides to get himself another cup of strong black coffee when men dressed in black suits walked into the research lab.

“All of you are to move away from the experiment right now, under the orders of the research management and the government”

One of the men stepped out of the crowd to identify themselves as government officials.

“Experiment #14 will be taken away from this research compound today. Another new subject will be assigned to this research team for the next round of testing. Thank you for your hard work and co-operation.” The man looked over to one of the men standing above Oikawa’s tank and nodded.

Hajime’s eyes widened when his stress-addled mind finally realized what was happening.

“Tranquilize it!”

Pop!

The tranquilizer shot out of the device and hit Oikawa’s shoulders. Slowly, the now merman, sunk down to the bottom of the small cylindrical tank, his eyes closing.

Iwaizumi saw red.

~~~~~~~

Special thanks to [Ambyrfire](http://archiveofourown.org/users/Ambyrfire/pseuds/Ambyrfire) for betaing this chapter

 

**Notes for the Chapter:**

> man Oikawa is such a pain to write. I decided to go for some Kagehina before moving my focus back to Oikawa.  
> I hope you enjoyed reading !  
> ~~~~~~~~~~  
> As for why I did not add the character death warning. I have my reasons. For example, I do not want to spoil certain deaths. Furthermore, in this story Daichi is not a character with a major role. Therefore, I find it unecessary to add Major Character death in the warnings. The fact that I CHOSE not to use archive warnings should have tipped you off. I also did tag Character death in the tags. Please read those tags before coming to complain to me. Thank you very much.


	4. Destroyed Dreams

**Summary for the Chapter:**

> The worst things come free to us

The worst things in life come free to us. No one was exempt from them. Not even Iwaizumi. Neither was Oikawa. They kept happening to him. He challenged them head on however. Doing his very best to defeat the odds. Oikawa, ever passionate when it came to Volleyball, the one hobby that had caught his full attention and brought him immense happiness whenever the tosses he made and serves which he threw, gained points began breaking him in when his kouhai of all people began over shadowing him, making him feel inferior. At one point, his tosses were not enough, his serves measly compared to that new genius that had come crashing in. Suddenly, he had become inadequate just because of a talented first year. And so, began the endless training. The painful grueling training schedules he made for himself. During those sessions, there was only one thing on his mind.

_Perfect the serves, perfect them and you own the court. Don’t let him get near you. Ever._

His teammates had watched, concern showing on their faces as he continued practicing and practicing without a care for what happened to his own body until one day he collapsed, one of his knees giving in under him, throbbing from immense pain. Wincing from the pain, Tooru had looked down at it angrily, and had begun sobbing as he looked down at the floor, defeated while thinking,

_Why am I never good enough? I hate this. I wish my knee won’t act up like this._

It felt like he was drowning. He didn’t care what was going on around him. He felt his team mates shake his shoulders or try to hug him to help calm him down. He felt tired, so tired of everything. The world was merely a blur as his surroundings swirled around him, suffocating him. He heard distant voices shouting his name. He closed his eyes and lay down and soon enough all he saw was black and then the comforting veil of unconsciousness.

 The very next day, he woke up in the hospital, nurses bustling around his bed and the scent of sanitary lotion and medicine invading his nostrils. He moved his head up and off the pillow only to be told to lie down once more for the nurses to check his vitals. His knee still hurt, the pain had reduced significantly but it still hurt enough to make him feel uncomfortable. Oikawa scanned the room quickly with his eyes and found that his parents weren’t there.

_Not surprising_

He had thought. His parents had never been bothered with him much anyways.

_Iwa chan would’ve cared….I miss him._

The thought crept up on him suddenly surprising himself. The memories of his long lost friend resurfacing in his mind. Memories of a time when he and Iwa chan played together and memories of him running away from the beetles that Iwaizumi oh so loved to catch.

_Iwa chan had been important to me hadn’t he? My only friend……He gave me that shiny blue stone he had found in the river a long time ago._

He smiled to himself a little, his little incident with the volleyball almost forgotten as he wrapped his arm around the bracelet he had made with said stone and closed his eyes.

Little did he know, that he was going to receive the most life changing news in his life in just a few hours.

“Oikawa Tooru, you have been selected for the special humanity survival project as a test subject under a contract, which your parents have already signed. In other words, you are now under the full control of the research committee in charge of the project. We look forward to working with you from now on.”

And in that moment, the words the government official said, had shattered his world and dreams completely. He had heard of friends being chosen for this project and knew that it was a very high honor to receive, to be able to help in ensuring humanity’s survival. However, it had never come across his mind that he of all people would be selected for such a prestigious project. He had lashed out and had screamed at the man, his eyes welling up with tears, “I WANT TO BE A VOLLEYBALL PLAYER AND AND BE THE BEST SETTER THERE IS AND –“

He was cut off by a sudden pain spiking from his right arm, a needle with a tranquilizer shot piercing through his skin. He fell like a lifeless doll on the hospital bed, helpless.

**Notes for the Chapter:**

> I was going to write more for this chapter but it ended at such an impactful sentence I decided to just leave it at that and post the continuation once I'm done writing it later.

**Author's Note:**

> Hope you enjoyed reading. I plan to continue and write a few more chapters. I'm not sure if I'll be able to finish this but I'll do my best!


End file.
